+2019-09-04 Mike Crowe <mac@mcrowe.com>
+
+ PR libstdc++/41861
+ * acinclude.m4 (GLIBCXX_CHECK_PTHREAD_COND_CLOCKWAIT): Check for new
+ pthread_cond_clockwait function.
+ * configure.ac: Use GLIBCXX_CHECK_PTHREAD_COND_CLOCKWAIT.
+ * configure: Regenerate.
+ * config.h.in: Regenerate.
+ * include/std/condition_variable: (condition_variable): Rename
+ __steady_clock_t typedef and add system_clock. Change __clock_t to be
+ a typedef for the preferred clock to convert arbitrary other clocks to.
+ [_GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT] (wait_until): Add a steady_clock
+ overload.
+ (wait_until): Change __clock_t overload to use system_clock.
+ [_GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT] (__wait_until_impl): Add
+ steady_clock overload that calls pthread_cond_clockwait.
+ (__wait_until_impl): Change __clock_t overload to use system_clock.
+ (condition_variable_any) [_GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT]: Use
+ steady_clock for __clock_t if pthread_cond_clockwait is available.
+
2019-09-04 Mike Crowe <mac@mcrowe.com>
* testsuite/30_threads/condition_variable/members/2.cc (test01):
AC_LANG_RESTORE
])
+dnl
+dnl Check whether pthread_cond_clockwait is available in <pthread.h> for std::condition_variable to use,
+dnl and define _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT.
+dnl
+AC_DEFUN([GLIBCXX_CHECK_PTHREAD_COND_CLOCKWAIT], [
+
+ AC_LANG_SAVE
+ AC_LANG_CPLUSPLUS
+ ac_save_CXXFLAGS="$CXXFLAGS"
+ CXXFLAGS="$CXXFLAGS -fno-exceptions"
+ ac_save_LIBS="$LIBS"
+ LIBS="$LIBS -lpthread"
+
+ AC_MSG_CHECKING([for pthread_cond_clockwait])
+ AC_CACHE_VAL(glibcxx_cv_PTHREAD_COND_CLOCKWAIT, [
+ GCC_TRY_COMPILE_OR_LINK(
+ [#include <pthread.h>],
+ [pthread_mutex_t mutex; pthread_cond_t cond; struct timespec ts; int n = pthread_cond_clockwait(&cond, &mutex, 0, &ts);],
+ [glibcxx_cv_PTHREAD_COND_CLOCKWAIT=yes],
+ [glibcxx_cv_PTHREAD_COND_CLOCKWAIT=no])
+ ])
+ if test $glibcxx_cv_PTHREAD_COND_CLOCKWAIT = yes; then
+ AC_DEFINE(_GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT, 1, [Define if pthread_cond_clockwait is available in <pthread.h>.])
+ fi
+ AC_MSG_RESULT($glibcxx_cv_PTHREAD_COND_CLOCKWAIT)
+
+ CXXFLAGS="$ac_save_CXXFLAGS"
+ LIBS="$ac_save_LIBS"
+ AC_LANG_RESTORE
+])
+
dnl
dnl Check whether sysctl is available in <pthread.h>, and define _GLIBCXX_USE_SYSCTL_HW_NCPU.
dnl
/* Define if pthreads_num_processors_np is available in <pthread.h>. */
#undef _GLIBCXX_USE_PTHREADS_NUM_PROCESSORS_NP
+/* Define if pthread_cond_clockwait is available in <pthread.h>. */
+#undef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+
/* Define if POSIX read/write locks are available in <gthr.h>. */
#undef _GLIBCXX_USE_PTHREAD_RWLOCK_T
+# For pthread_cond_clockwait
+
+
+
+ ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+ ac_save_CXXFLAGS="$CXXFLAGS"
+ CXXFLAGS="$CXXFLAGS -fno-exceptions"
+ ac_save_LIBS="$LIBS"
+ LIBS="$LIBS -lpthread"
+
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for pthread_cond_clockwait" >&5
+$as_echo_n "checking for pthread_cond_clockwait... " >&6; }
+ if ${glibcxx_cv_PTHREAD_COND_CLOCKWAIT+:} false; then :
+ $as_echo_n "(cached) " >&6
+else
+
+ if test x$gcc_no_link = xyes; then
+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+#include <pthread.h>
+int
+main ()
+{
+pthread_mutex_t mutex; pthread_cond_t cond; struct timespec ts; int n = pthread_cond_clockwait(&cond, &mutex, 0, &ts);
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+ glibcxx_cv_PTHREAD_COND_CLOCKWAIT=yes
+else
+ glibcxx_cv_PTHREAD_COND_CLOCKWAIT=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+else
+ if test x$gcc_no_link = xyes; then
+ as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5
+fi
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+#include <pthread.h>
+int
+main ()
+{
+pthread_mutex_t mutex; pthread_cond_t cond; struct timespec ts; int n = pthread_cond_clockwait(&cond, &mutex, 0, &ts);
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_link "$LINENO"; then :
+ glibcxx_cv_PTHREAD_COND_CLOCKWAIT=yes
+else
+ glibcxx_cv_PTHREAD_COND_CLOCKWAIT=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+ conftest$ac_exeext conftest.$ac_ext
+fi
+
+fi
+
+ if test $glibcxx_cv_PTHREAD_COND_CLOCKWAIT = yes; then
+
+$as_echo "#define _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT 1" >>confdefs.h
+
+ fi
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_PTHREAD_COND_CLOCKWAIT" >&5
+$as_echo "$glibcxx_cv_PTHREAD_COND_CLOCKWAIT" >&6; }
+
+ CXXFLAGS="$ac_save_CXXFLAGS"
+ LIBS="$ac_save_LIBS"
+ ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+
ac_fn_c_check_header_mongrel "$LINENO" "locale.h" "ac_cv_header_locale_h" "$ac_includes_default"
if test "x$ac_cv_header_locale_h" = xyes; then :
# Check for tmpnam which is obsolescent in POSIX.1-2008
GLIBCXX_CHECK_TMPNAM
+# For pthread_cond_clockwait
+GLIBCXX_CHECK_PTHREAD_COND_CLOCKWAIT
+
AC_LC_MESSAGES
# For hardware_concurrency
/// condition_variable
class condition_variable
{
- typedef chrono::system_clock __clock_t;
- typedef chrono::steady_clock __steady_clock_t;
+ using steady_clock = chrono::steady_clock;
+ using system_clock = chrono::system_clock;
+#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+ using __clock_t = steady_clock;
+#else
+ using __clock_t = system_clock;
+#endif
typedef __gthread_cond_t __native_type;
#ifdef __GTHREAD_COND_INIT
wait(__lock);
}
+#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+ template<typename _Duration>
+ cv_status
+ wait_until(unique_lock<mutex>& __lock,
+ const chrono::time_point<steady_clock, _Duration>& __atime)
+ { return __wait_until_impl(__lock, __atime); }
+#endif
+
template<typename _Duration>
cv_status
wait_until(unique_lock<mutex>& __lock,
- const chrono::time_point<__clock_t, _Duration>& __atime)
+ const chrono::time_point<system_clock, _Duration>& __atime)
{ return __wait_until_impl(__lock, __atime); }
template<typename _Clock, typename _Duration>
wait_until(unique_lock<mutex>& __lock,
const chrono::time_point<_Clock, _Duration>& __atime)
{
- // DR 887 - Sync unknown clock to known clock.
const typename _Clock::time_point __c_entry = _Clock::now();
const __clock_t::time_point __s_entry = __clock_t::now();
const auto __delta = __atime - __c_entry;
wait_for(unique_lock<mutex>& __lock,
const chrono::duration<_Rep, _Period>& __rtime)
{
- using __dur = typename __steady_clock_t::duration;
+ using __dur = typename steady_clock::duration;
auto __reltime = chrono::duration_cast<__dur>(__rtime);
if (__reltime < __rtime)
++__reltime;
- return wait_until(__lock, __steady_clock_t::now() + __reltime);
+ return wait_until(__lock, steady_clock::now() + __reltime);
}
template<typename _Rep, typename _Period, typename _Predicate>
const chrono::duration<_Rep, _Period>& __rtime,
_Predicate __p)
{
- using __dur = typename __steady_clock_t::duration;
+ using __dur = typename steady_clock::duration;
auto __reltime = chrono::duration_cast<__dur>(__rtime);
if (__reltime < __rtime)
++__reltime;
- return wait_until(__lock, __steady_clock_t::now() + __reltime,
+ return wait_until(__lock, steady_clock::now() + __reltime,
std::move(__p));
}
{ return &_M_cond; }
private:
+#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+ template<typename _Dur>
+ cv_status
+ __wait_until_impl(unique_lock<mutex>& __lock,
+ const chrono::time_point<steady_clock, _Dur>& __atime)
+ {
+ auto __s = chrono::time_point_cast<chrono::seconds>(__atime);
+ auto __ns = chrono::duration_cast<chrono::nanoseconds>(__atime - __s);
+
+ __gthread_time_t __ts =
+ {
+ static_cast<std::time_t>(__s.time_since_epoch().count()),
+ static_cast<long>(__ns.count())
+ };
+
+ pthread_cond_clockwait(&_M_cond, __lock.mutex()->native_handle(),
+ CLOCK_MONOTONIC,
+ &__ts);
+
+ return (steady_clock::now() < __atime
+ ? cv_status::no_timeout : cv_status::timeout);
+ }
+#endif
+
template<typename _Dur>
cv_status
__wait_until_impl(unique_lock<mutex>& __lock,
- const chrono::time_point<__clock_t, _Dur>& __atime)
+ const chrono::time_point<system_clock, _Dur>& __atime)
{
auto __s = chrono::time_point_cast<chrono::seconds>(__atime);
auto __ns = chrono::duration_cast<chrono::nanoseconds>(__atime - __s);
__gthread_cond_timedwait(&_M_cond, __lock.mutex()->native_handle(),
&__ts);
- return (__clock_t::now() < __atime
+ return (system_clock::now() < __atime
? cv_status::no_timeout : cv_status::timeout);
}
};
// Like above, but mutex is not required to have try_lock.
class condition_variable_any
{
- typedef chrono::system_clock __clock_t;
+#ifdef _GLIBCXX_USE_PTHREAD_COND_CLOCKWAIT
+ using __clock_t = chrono::steady_clock;
+#else
+ using __clock_t = chrono::system_clock;
+#endif
condition_variable _M_cond;
shared_ptr<mutex> _M_mutex;